WARNING: This article contains spoilers for Uncanny X-Men #2, by Ed Brisson, Matthew Rosenberg, Kelly Thompson, R.B. Silva, Adriano di Benedetto, Rachelle Rosenberg, and Joe Caramagna, on sale now.

The X-Men have a lot going on right now. Over the past two issues of Marvel's recently-relaunched, weekly Uncanny X-Men, they've had to search for missing teammates, deal with a reformed Mutant Liberation Front, investigate mysterious weather phenomena, fight a horde of ranting Multiple Man duplicates, and go toe-to-claw with dinosaurs in Montana.

And now, Legion, one of Marvel's most powerful mutants, just showed up on the X-Mansion's doorstep on the last page of Uncanny X-Men #2. After getting trounced by the Mutant Liberation Front in Uncanny X-Men #1, a group of young X-Men are licking their wounds at the Xavier Institute for Mutant Education and Outreach. In the middle of a giant anti-mutant protest at the X-Mansion, Legion emerges from the crowd and introduces himself to the X-kids with a slick new haircut and an uncharacteristically sharp suit.

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Legion Return Uncanny X-Men

It's been a little while since Professor X's wayward son encountered the X-Men, but important things tend to happen whenever he comes across the heroes fighting for Xavier's dream. Long before Legion became the unlikely star of his own live-action TV show, he was just David Haller, the son of Charles Xavier and his former patient Gabrielle Haller. But shortly after he was created by Chris Claremont and Bill Sienkiewicz in 1985's New Mutants #25, Legion's telepathic mutant powers emerged during a terrorist attack that took his mother's life.

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In a somewhat controversial twist that largely defined the character, Legion developed hundreds of alternate personas, each of which controlled a portion of his vast powers. After a few early encounters with the New Mutants, Legion ended up on Muir Island, where the Shadow King, the X-Men's biggest telepathic villain, briefly took over the young mutant's body and left him in a vegetative state.

In what's arguably his most famous story, Legion traveled back in time to kill Magneto before he became a villain in the 1994 crossover "Legion Quest." When a young Xavier died taking the attack meant for his friend, Legion inadvertently created a new timeline that was explored in "Age of Apocalypse," one of the X-Men's most popular 1990s stories.

Legion New Mutants

After bouncing around the X-books for years, Legion finally got a starring role in 2013's X-Men: Legacy, where he tried to bring his powers and personalities together in a way that honored his father's dream.

Although that series ended with Legion trying to erase himself from reality, David returned earlier this year in Legion, a miniseries by Peter Milligan, Wilfredo Torres and Lee Ferguson. With the help of psychologist Hannah Jones, Legion apparently dealt with his forceful new persona, Lord Trauma.

While Legion usually has a towering, gravity-defying mound of hair, he has his hair down in a more natural, relaxed look in Uncanny X-Men #2. While it's unclear if this reveals anything about Legion's current mental state, it's worth noting that Lord Trauma wore his hair in a very similar fashion in Legion, so there's a chance Trauma may very well be in control of Legion's body and powers right now.

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Given his foundational role in establishing the Age of Apocalypse timeline, there's a solid chance Legion will also play a role in the upcoming "Age of X-Man" storyline. While details are still scarce, that story will apparently center around Nate Grey, a powerful mutant who was born in the dystopian Age of Apocalypse world.

Someone has already begun hunting down villains from that alternate reality, and it's hard imagine Legion not having a role in the event, especially given the timing of his return. While it's not clear whether Legion is a mastermind or just another pawn, his return is just another thing the X-Men will have to deal with as the weekly "X-Men Disassembled" storyline continues to unfold.